stilbenes and tanshinone

Hepatocellular carcinoma (HCC) is one of the most prevalent malignancies worldwide. The clinical management of HCC remains a substantial challenge. Although surgical resection of tumor tissues seems promising, a high recurrence and/or metastasis rate accounting for disease-related death has led to an urgent need for improved postsurgical preventive/therapeutic clinical intervention. Developing advanced target-therapy agents such as sorafenib appears to be the only effective clinical intervention for patients with HCC to date, but only limited trials have been conducted in this regard. Because of their enhanced preventive/therapeutic effects, traditional Chinese herbal medicine (CHM)-derived compounds are considered suitable agents for HCC treatment. The CHM-derived compounds also possess multilevel, multitarget, and coordinated intervention effects, making them ideal candidates for inhibition of tumor progression and HCC metastasis. This article reviews the anticancer activity of various CHMs with the hope of providing a better understanding of how to best use CHM for HCC treatment.

Topics: Abietanes; Benzylisoquinolines; Berberine; Carcinoma, Hepatocellular; Curcumin; Drugs, Chinese Herbal; Humans; Liver Neoplasms; Medicine, Chinese Traditional; Resveratrol; Scutellaria baicalensis; Stilbenes

Dibenzo[a,l]pyrene (DBP) has been found to be the most potent carcinogen of the polycyclic aromatic hydrocarbons (PAHs). Primary sources for DBP in the environment are combustion of wood and coal burning, gasoline and diesel exhaust, and tires. Given the likelihood of environmental exposure to DBP and strong experimental evidence of its potency, it is likely to contribute to lung cancer development. Intervention with compounds of natural origin ("phytochemicals") is considered an effective means to prevent cancer development and favorably modulate the underlying mechanisms, including DNA adduct formation. In this study, several agents have been identified that inhibit environmental carcinogen-induced DNA adduct formation using a cell-free microsomal system. Of the ten agents tested, resveratrol (648 ± 26 adducts/10(9) nucleotides), oltipraz (1007 ± 348 adducts/10(9) nucleotides), delphinidin (1252 ± 142 adducts/10(9) nucleotides), tanshinone I (1981 ± 213 adducts/10(9) nucleotides), tanshinone IIA (2606 ± 478 adducts/10(9) nucleotides) and diindoylmethane (3643 ± 469 adducts/10(9) nucleotides) were the most effective compared to vehicle treatment (14,062 ± 1097 adducts/10(9) nucleotides). DBP is metabolized by phase I metabolizing enzymes CYP1A1, CYP1A2, and CYP1B1. DBP-induced DNA adducts can be inhibited by several mechanisms. We found that all the test agents inhibited DNA adducts by inhibiting one or more of these enzymes. Oltipraz inhibited DNA adducts entirely by inhibiting the CYP450s, while resveratrol and delphinidin inhibited DNA adducts by also interacting directly with the carcinogenic metabolite, anti-dibenzo(a,l)pyrene-11,12-dihydrodiol-13,14-epoxide.

Topics: Abietanes; Animals; Anthocyanins; Benzopyrenes; Carcinogens; Cytochrome P-450 CYP1A1; Cytochrome P-450 CYP1A2; Cytochrome P-450 CYP1B1; DNA Adducts; Indoles; Microsomes, Liver; Phytochemicals; Rats; Resveratrol; Stilbenes

To determine the combinative effects of tanshinone IIA (Tan IIA) and trans-resveratrol (Resv) on cytotoxicity, apoptosis, cell-cycle arrest and DNA fragmentation in HepG2 human liver cancer cells.. Cytotoxicity was detected by the cell proliferation and cytotoxicity WST-1 assay. Cell-cycle arrest and apoptosis were determined using flow cytometry analysis. DNA fragments were separated by gel electrophoresis.. Tan IIA and Resv at mixture ratios of 1/2:1/2 and 1/3:2/3 exerted synergistic cytotoxicity comparable to that of cisplatin. Elevated proportions of sub-G1 and apoptotic cells were respectively found in the combinative treatments in comparison with hypothetic values of additive effects. Moreover, a more intensive pattern of apoptotic DNA fragmentation was visualized in combined treatments than in individual ones.. Combining Tan IIA and Resv causes synergistic cisplatin-comparable, cytotoxicity and robustly induces apoptosis, sub-G1 cell cycle arrest and DNA fragmentation. This study provides evidence supporting further pre-clinical investigations of the combinational synergism.

Topics: Abietanes; Apoptosis; Cell Cycle Checkpoints; Cell Survival; Cisplatin; DNA Fragmentation; Drug Synergism; Hep G2 Cells; Humans; Inhibitory Concentration 50; Resveratrol; Stilbenes